As money — or at least record sales — evaporates from the music business, it's been clear for a while now that the new economy is attention. Though the crown gets passed around, pop stars consistently top Twitter and Facebook's most-followed lists, and artists from Lady Gaga to Beyonce to Radiohead have spent the smartphone era striving for ways to set themselves apart that have little to do with singing or songwriting.

Music’s capacity for shock factor is older than Elvis’ hips, but this year’s seen some eye-opening efforts, from Lady Gaga’s SXSW vomit-art to the independent band Vulfpeck scoring around $20,000 from a silent Spotify release that punk’d the streaming service’s poor royalty format. The right concept can go viral -- but the wrong one can flop badly, as Gaga's Warhol-inspired "Artpop" has.

Breaking new ground every time out is hard, if not eventually impossible — even David Bowie’s 2013 surprise album retreads his glory days — and recent pop has been moving past its shock escalation into a more sustainable trick: the collaboration. Artist pairings have a long history, too, and for good reason: bringing two musicians together for a one-off song doubles the fan base. Less cynically, it gives musicians the chance to shake off the expected and try out each other’s territory, sometimes to remarkable results and sometimes to “Accidental Racist.”

While a staple of modern hip-hop, this summer has been packed with guest spots all over: the posse gathered on Chris Brown’s “Loyal,” the Charli XCX invasion of Iggy Azalea’s “Fancy,” and Azalea’s own slide into Ariana Grande’s “Problem” have all made for major hits.

It sounds like we’re only getting started: next up is “Bang Bang,” a track from UK crossover hopeful Jessie J, who corrals Grande and the ever-aflame Nicki Minaj, who’s gearing up for her own next album. As the kids might say, Minaj dropped the most fire guest verse of the last decade on Kanye West’s “Monster,” and she’s commanding here, speeding through rhymes until reaching “Queen Nicki, dominant, prominent” and dropping back to a less athletic speed. The powerhouse Grande’s contribution is serviceable but short: J is the star here, and the British singer wails through the opening verse and a voluminous chorus that Xeroxes her voice until it fills up the track like Grammys in Adele’s sock drawer.

“Bang Bang,” a PG track about sex aimed at the radio, a Disney-age audience and only half-heartedly at the club, flounders lyrically, promising pleasure while still staying a “good girl” — rather than crash through the good-bad binary in the way Minaj has been lately. I can’t say it’s much of a song, but the fun here is in listening to three very different divas team up for a day, none willing to take an eye off the throne. Who knows where they’ll turn up next?